Accelerator hydraulic holding units



Dec. 16, 1958 w 2,864,352

ACCELERATOR HYDRAULIC HOLDING UNITS Filed 001:. 9, 1956 2 Sheets-Sheet 1FIG. 3

mu/Enrol? T/IOMAS E WZL5 5 9 162 Jug A TTORNEY T. E. WELLS 2Sheets-Sheet 2 nvvavrop THOMAS E. WELLS n BY W ATTORNEY Dec. 16, 1958ACCELERATOR HYDRAULIC HOLDING UNITS Filed Oct. 9. 1956 2 G H M 3V ealiwr f C v4 nv/ x A C \\\\\/Si\ United This invention relates to automobileand truck acceleraion systems and more particularly to an acceleratorholding unit.

In conventional accelerator systems of today, the driver of a movingvehicle must maintain his right foot in a tensed position to overcomethe tendency of this foot to relax downwardly on the accelerator pedal,thus dangerously increasing the speed of the vehicle. One of the mainobjectives of the present invention is to transform this tendency from adetriment to an asset by permitting a driver to relax and thus rest hisright foot on the accelerator pedal while the fuel or accelerator systemof his engine is held at any desired rate by a novel sealed hydraulicholding unit. The hydraulic holding unit of the present invention ischeap to construct and easy to install and is so designed that it canreadily and ideally be incorporated into the acceleration systemsconventionally employed today.

Another objective of the present invention is to permit the operator ofa vehicle to experience a feeling of real control while driving byenabling him to while in a relaxed state rest his foot downwardly on theaccelerator pedal while still maintaining a uniform and constant vehiclespeed. Also the right foot and leg of the normal driver, with the use ofthe present invention is less likely to become tired, the driver willhave better use of it during emergencies and will also be less likely toresort to the unsafe practive of using a hand throttle control which isoften the case.

. Still another objective of the present invention is to permit aninstantaneous release of the holding action and a reverting toconventional accelerator control without the use of the brake pedal,which is the usual way this is accomplished in other holding devices ofthis type. The driver will then be in a much more favorable position todecelerate during average driving conditions and particularly duringemergencies. Also because the present invention requires the driver tokeep his footon the accelerator pedal at all times to maintain thedevice in its holding sequence, it further assures that the right footwill be in its proper position to operate the brake pedal in case ofnecessity.

These and other beneficial advantages will become manifest as theinvention is further disclosed.

Now referring to the accompanying drawings forming a part of thisapplication,

Figure 1 is a schematic View of the present accelerator hydraulicholding unit incorporated in a conventional accelerator system,

Figure 2 is an isometric cutaway view of the accelerator holding unitwith the main check valve and piston in the non holding or openposition, and

Figure 3 is a partial vertical section of Figure 2 showing the pressurechamber with its parts in a holding or closed position.

Once again referring to Figure 1 the main body 34 of the sealedhydraulic unit is shown interposed in a conventional accelerator systemconsisting essentially of an accelerator pedal 14 which by means of thelinkage shown actuates a butterfly fuel control valve 30 for regulatingthe speed of a vehicle. This linkage consists of footpedal connectingrod 16, bell crank 17, hinged link rod 18, sliding block 19, compressionspring 20, main link rod 1 which is connected to and through main body34 of the sealed hydraulic unit as hereinafter described, as well as tobell crank 27, connecting rod 28, and a butterfly fuel control valve 30.Return spring 31 is attached in the conventional system to bell crank 27and connecting rod 28 to urge the butterfly valve 30 to its closedposition and at the same time to urge the accelerator foot pedal 14,through the shown linkage, upwardly to its deceleration position. Theentire system as shown here can be easily and readily incorporated inthe motor vehicle in present use.

Figure 2 shows the isometric cutaway view of the preferred embodiment ofthis invention. Connecting rod 1 of the linkage system shown in Figure 1is shown to be an integral part of connecting block 13 which in turn isconnected to ported piston 11 by piston connecting rod 12. Movement ofconnecting rod 1 then imparts movement to the piston rod 12 and hence tothe ported piston 11 and to the following cup 10A and the disc 10, whichis merely a rigid backing disc to give stability to the resilient orflexible follower cup 10A. It will be noticed that the disc 10 whileattached to following cup 10A is not attached to ported piston 11 and isfree to move independently from it.

The hydraulic liquid level 26 of the hydraulic liquid body 36, whichliquid can be brake oil or the like, is shown in Figure 3 to be someWhat above the pressure chamber 9. The entire pressure chamber 9 isimmersed in and filled with this hydraulic liquid. The hydraulic liquidfills piston cylinder 9A on both sides of ported piston 11, follower cup10A and disc 10, with follower cup 10A as a sealer.

With the entire pressure chamber 9 including piston cylinder 9A filledwith hydraulic fluid it is apparent that as the accelerator pedal 14 ispressed downwardly in the conventional manner, this movement istransmitted through link rod 1 to ported piston 11 and follower cup 10A,and results in the oil being compressed out of piston cylinder 9Athrough liquid outer channel 9B into main pressure chamber 9, aroundopen check valve 6, and through the ports in combination valve seat andguide ring 8 and out into the main oil reservoir 36. This flow ofhydraulic liquid is reversed on deceleration. Figure 2 shows the checkvalve 6 in its opened position, while Figure 3 shows it in its closedposition.

As the ported piston 11 is drawn back on the deceleration stroke of linkrod 1, spring 24 is provided in the piston cylinder 9A to returnfollower cup 10A and backing disc 10 to its position against the portedpiston 11, as they are not connected to the ported piston 11 and arefree to move independently thereof. Ported piston 11 is provided withports or channel openings 11A to permit the hydraulic liquid to flowfrom one side of the ported piston 11 to the other. This is a safetyfeature in the event the resilient follower cup 10A and backing disc 10cannot move due to a vacuum or pressure being created behind disc 10 dueto the independent movement of ported piston 11. Resilient follower cup10A forms a seal however in piston cylinder 9A to prevent hydraulicfluid from passing from one side of it to the other. The backing disc 10gives the necessary strength to follower cup 10A to prevent it cockingin the piston cylinder 9A and to absorb the contacting force from portedpiston 11.

To clarify the structure of the hydraulic chamber 34, it can be seenfrom Figure 2 that the entire pressure chamber 9 is completely sealedfrom the main oil body.

36 by means of casing 36a. There are only three outlets between the mainoil body and the pressure cham her 9. One outlet is through portedpiston 11 to piston cylinder 9A whichis sealed ,by follower cup 10A. Thesecond is the opening in the top of the pressurechamber sealed byrelease valve 22,-and the third .is the opening also in-the top of thepressure ,chamber shown in the valve seat and guide ring 8whichopeningcanbenclosed by check valve 6.

When it .is desired to :put thehydraulic ,unit in operatron so as toenable the driver to restthis foot and leg downward without changing hisfuel setting, all that is required in the presentinvention ,is for himto close the floor board switch ,2 as shown in Figure 1 with his leftfoot and [thento allow his right'foot to relax downward on theaccelerator pedal 14. As switch 2 closes, electrical current flowsthrough wires .33 to solenoid coil ,3 and grounding through wire 32causingsolenoid coil 3 to ,be energized, which in turn pulls iron core4, valve stem ,5 and check valve 6 upwards, compressing light spring 7between plate E and washer F until upper face 6A of check valve 6contacts the face of combination valve seat and guide ring 8. Thisclosing of the check valve 6 then makes pressure chamber 9 oil tight andprevents anyforward (acceleration) movement of follower. cup 10A anddisc 10, ported piston 11,-connecting,rod 12,, Qonnecting block 13 andlink rod 1. As soon as the driver has actuated the solenoid switch 2, heimmediatelyallows his right foot to relax downward on pedal 14. Thisadditional force working through pedal 14, pedal rod 16,'bell crank 17,link rod 18 and sliding block 19, will then cause sliding block 19 toslip forward on link rod 1. As link rod 1 now is stationary, spring20tis compressed between the sliding block 19 and the pinned washer 21until the compressed spring force is equal to the jforceof'the weight ofthe drivers foot or until the pedal 14 contacts heavy resting spring 15.In any event any additional pressure being applied on the confinedhydraulic fluid in the pressure chamber9 by the weight of thedriversjfoot working through pedal 14, rod 16, bell crank ILlink rod 18,sliding block 19, spring 20, link rod 1, connecting block 13, connectingrod 12, piston 11 and follower cup 10A and disc 10 will be magnified inthe preferred embodiment approximately times, due to the area of checkvalve 6 being approximately this much greater than the area of thefollower cup A. This pressure will then be more than sufficient to holdcheck valve 6 in the closed position and therefore the driver will beable to remove his left foot from said solenoid switch "2, breaking theelectrical circuit and de-energizing the solenoid coil and stillkeep thedevice in thetholding sequence.

If the device'has been set and the driver wishes to accelerate hisengine such as for passing or climbing a'hill, this may be done in twoways; one of which is'by pushing heavily with his foot on theaccelerator pedal 1.4, which will then depress the resting spring andwill .then contact the end of cable37, forcing it throughitshousing,causing the cable to force valve stem guide B downward against spring K,causing stem H to open release valve'22 which is normally in a closedposition. Oil in chamber9 and cylinder 9A will then be 'freetoflowaround release valve 22, up into the middle of valve body 23 and outinto the main oilreservoir 36, through holes 23A, which holes arelocated in thebody 23 of the release valve'22. These holes may be of.anydesired size to enable the release of the oil and the speed ,with whichthecarburator butterfly may be opened to be, predetermined. This releaseof oil will then allowthe force of compressed spring to move washer21,link rod 1, connecting block'13, rod 12, piston 11, and follower cup10A and disc 10 ahead'to the accelerate position. The second way is forthe driver to lift his foot from the acceleratorthus permitting thepedal'14 to move upward towards the decelerated-position until thepressure is reduced ontheface of check valve 6 sufliciently to allow thenatural weight, of check valve 6, stemS, and iron core 4, plus the'forceof light compressed spring 7 to cause the check valve 6, stem, and coreto promptly move downward to its normal open position thus permittingthe accelerating system to again operate freely as the locking featureof the device is then inoperative. The accelerator pedal 14, rod 16,bell crank 17, hinged link rod 18, block 19, link rod 1, bell crank 27,connecting rod '28, and lever 29 with attached carburator butterfly30for controlling thetvehicle fuel supply will then be free to operatein a normal fashion until theldeviceis again set by depressing solenoidswitch ,2 and resting the foot downward on pedal 14. It should beemphasized that this freeing action is for all practical purposesinstantaneous with the lifting of the foot from the accelerator.

It is manifest that what has already been described is a new andimportant improvement in holding units for acceleration systems andchanges and alterations can be made to thisholding unit whilestillremaining within the purview of this invention. Therefore, what isnow claimed is as follows:

1. In a vehicle acceleration system of the class described a sealedhydraulic unit interposed on the normal vehicle linkage between theaccelerator foot pedal and the butterfly fuel control valve; said sealedhydraulic unit having, a main hydraulic chamber partially filled withsuitable hydraulic liquid, a pressure chamber in said main hydraulicchamber, and said pressure chamber beingfilled with and'immersed beneathsaidhydraulic liquid, a check valve in said pressure chamber sealing anopening between said main hydraulic chamber and said pressure chamber,spring means on said check valve for downwardly urging said check valveinto an unsealedor opened position to permit the free flow of saidhydraulic liquid from said pressure chamber to said main hydraulicchamber, a release valve in said pressure chamber sealing an openingbetween said pressure chamber and said main hydraulic chamber; springmeans urging said release valve upwardly into a sealed or closedposition; a piston cylinder section in said pressure chamber, a movablepiston operable in said piston cylinder section, spring means withinsaid piston cylinder section urging said piston outwardly into itsdecompressing position, direct connecting means between said movablepiston and said normal vehicle acceleration linkage, a hydraulic liquidoutlet channel between said piston section and said pressure chamber;electrical closing means on said check valve for lifting said checkvalve to its sealed or closed position; mechanical opening means forexternally forcing said release valve downwardly into an unsealed oropen position and contact means on the floor board of a vehicle foroperating .said check valve electrical closing means and saidreleasevalve mechanical opening means.

2. The same as claim 1 with the said electrical closing means for saidcheck valve being a solenoid, a center iron core movable withinsaidsolenoid, a shaft connecting means between said check valve and saidcenter iron core to enable said solenoid when energized to lift saidcheck valve; a suitable electrical wired circuit to and from saidsolenoid, and a suitable foot switch located on the-foot board of avehicle for operating said electrical circuit.

3. The same as claim 1 with said mechanical opening means'for saidrelease valve being a cable extending from the floor board of saidvehicle to said release valve, and a foot contact means with said cablefor forcing said release valve open.

4. The same as claim 1 withvsaid piston operating in said pistoncylinder having ports or channel openings from one side of thepiston tothe other to permit the free flow of hydraulic liquid from one side tothe other, and .a resilient .follower cup positioned aheadof said pistonfor slidably moving within said piston cylinder section and, sealing offthe flow of hydraulic liquid-frorn one side of said follower cup to theother, and said follower cup being freeof and not attached to saidpiston.

5.. The same as claim 2 with said mechanical opening means for saidrelease valve being a cable extending from flow of hydraulic liquid fromone side of said follower the fioorboard of said vehicle to said releasevalve, and cup to the other, and said follower cup being free of and afoot contact means with said cable forcing said release not attached tosaid piston.

valve open; and said piston operating in said piston cylinder havingports or channel openings from one side of References Cited in the fileof this 13am1t the piston to the other to permit the free flow ofhydraulic UNITED STATES PATENTS liquid from one side to the other and aresilient follower cup positioned ahead of said piston for slidablymoving 2,533,836 Patterson Dec. 12, 1950 within said piston cylindersection and sealing off the 2,709,993 Kulhavy June 7, 1955

